Because of upgrades to WordPress that were mandatory, there has been a problem where code has disappeared. We are now using the Artiss YouTube Embed plugin.
To use it, just do what you did before to embed YouTube code (using the “old” embed code and using 525 pixel width), but wrap with the Artiss YouTube Embed code. I can’t use the text here because it will just be invsible, so I did a screenshot of what the wrap code should look like…
That’s all there is to it! Just add the tags before and after your “old” embed code and your code should be fine.